a flip-flop or latch is a circuit that has two stable states and can be used to store state information.

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Unsure if this asynchronous D-Flip-Flop Verilog code makes sense

This is my code for an async-reset-set D-flip-flop. I'm using quartus, and the module compiles, but there is no way to check if my logic is valid. I could use some outside opinions. The reset is ...
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1answer
90 views

problem with making 1 bit RAM memory using transistors?

I'm trying to make 1 bit RAM using four transistor ( 2 NOR Gates ). I built the 2 copies of the following circuit: I connected a LED to the output "F". Also, I connected Another LED to the output ...
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3answers
118 views

Reset of a JK flip flop pulse indicator

I've made a circuit with 74HC109 JK flip flops. The purpose is to catch a pulse from two signals and for about 20 seconds keep the stored value (of which pulse came first). My problem is I need to ...
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3answers
39 views

Powering on specific pieces of circuitry in sequence

I'm trying to power on specific pieces of circuitry in sequence, and have one piece active at a time. I thought a decade counter would be the way to go but most people seem to think a decade counter ...
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4answers
75 views

JK Flip Flop toggle action

How does toggle action in a JK flip flop change to alternate states? When both inputs are 1 ,the output of nor gates is forced to 0,then how come they toggle ?
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1answer
27 views

How to initiate Preset and Clear in a JK flip flop?

I want to use a JK flip flop in order to create a toggle output. It is clear that both J and K should be set to 1, as well as the Preset and Clear inputs. In some schematics, a Monostable 555 ...
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2answers
104 views

Generate flip-flops using only combinational logic

Just for fun, I wanted to design and simulate D-type flip-flops using only combinational logic in Verilog (or SystemVerilog). I am using using Verilator for the simulation. My initial attempt, which ...
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2answers
173 views

BJT Astable Multivibrator

I have the basic knowledge about multivibrators, but I did not understand the working principles of the circuit schematic provided down below. I have done the basic research about how it works, but ...
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1answer
95 views

NAND gate in proteus

I am trying to make a JK flip flop circuit in proteus but 2 of the nand gates does not seem to be working. There are no errors provided. Two of the 2-input nand gates does not seem to show output ...
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2answers
46 views

VHDL - Flip Flop inferring on a signal

I have to design a circuit to count up to a number and return to zero. It must have a carry signal (which I named a_o in my circuit) as flag to show that the ...
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1answer
300 views

JK flip flop random start outputs

I am working on a project for college and I have to implement a sort of alarm using only MUX's and JK flip flops and a bread board. The problem I encountered is that whenever I power the whole circuit ...
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5answers
130 views

Understanding D flip flop function - what this thing does

I am trying to understand what a D flip flop does int he context of building a truth table, so I can design a synchronous divide-by-five circuit. That is, count to five and reset. I know I need 3 ...
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2answers
57 views

Unable to toggle SN74HC109

I'm a complete amateur, I've probably gotten a million things wrong with this already. I'm using an SN74HC109 dual j-k" flip-flop chip. I'm trying to toggle the led (forgot to add a resistor in the ...
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1answer
70 views

JK Flipflop design for conveyor project

I have a small project/problem I am working on. While running a conveyor belt continuously with items on it, I need to stamp every other item. I am using a photocell to detect if an item is ...
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1answer
68 views

momentary to on/off switch for 12v

I got some oem switches and I want to mod them into light switches. Here is my situation: I would like to use the oem switch since it has illumination and button that matches the car.I have already ...
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1answer
78 views

Proteus BJT Astable Multivibrator Simulation Error

I am pretty new in Proteus and made a simple flip flop circuit as shown below. When I run the simulation, the circuit does not work as intended. Both of the LEDs light up at the same time. (LEDs ...
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1answer
88 views

How do I find the Truth Table for Mealy State Machine?

This is a followup to my previous question: I have this assignment in college: You are to design a Mealy state diagram for a safety device. Assume that two debounced push-buttons, A and B, are ...
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1answer
81 views

Mealy Safety Device with 2 inputs

I have an assignment in college and I would like to ask some questions: You are to design a Mealy state diagram for a safety device. Assume that two debounced push-buttons, A and B, are available ...
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1answer
59 views

Sequence detector

I have a few questions to ask about electronics.I am studying computer science in my first year and I have a logic design course where the professor is kind of old let's say and he expects us to study ...
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3answers
145 views

Need help in understanding MUX-NOT flip-flop

I need help in doing practice problem: A MUX-NOT flip-flop (MN flip-flop) behaves as follows. If M=1 the flip-flop complements the current state. If M=0, the next state of the flip-flop is equal to ...
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1answer
43 views

Need help with pspice simulation

I made a project of monostable flip flop using 555 timer in pspice. Now I need help with simulation. Problem is that I'm just statring my adventure with pspice and I have no clue what I'm doing wrong. ...
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1answer
52 views

D flipflop in keypad

Why D flipflop is used in keypad for LCD ( U2 in schematic shown below ). Is it for buffer? unidirectional or bidirectional?
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47 views

24 Hour Counter JK Flip Flop

I'm trying to implement a 24 hour clock circuit using JK Flip Flops. I've gotten the minute part but I am having trouble designing the hours part, specifically the ones section. If it should count ...
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1answer
81 views

Mealy machine to detect sequence of 2 inputs

I have the following assignment for a project at college and I have a few questions regarding it. You are to design a Mealy state diagram for a digital lock. Assume that two debounced push-buttons, A ...
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2answers
57 views

Building circuit for n-relays using flip flops, is this the best solution?

I'm trying to build a circuit for n relays, each relay should hold it's state (ie latched). My first Idea was to use decoders, but clearly this was a bad option, since the state of the relays won't ...
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1answer
101 views

How would you make a 3-bit binary adder that adds two instead of 1?

I am trying to make an asynchronous adder that holds three bits and adds two to the number. Can someone help? A Google search shows nothing and I'm having a hard time visualizing how to make the ...
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39 views

Kmap Implementation in Electronics Workbench

I'm working in Electronics Workbench and after simplifying two of the Kmaps, I got values : Jd=1 & Kd=1 How would I implement that in the circuit? I know it looks confusing at the moment.
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1answer
100 views

LFSR Using D Flip Flops

I am fairly new to the VHDL language and I will admit that I primarily use it for educational purposes. I have been attempting to design a data encryption circuit using D flip flops. Obviously, an ...
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1answer
41 views

Help designing a serial adder [closed]

I need to build a circuit that adds two n-bit 2's complement numbers. the two numbers have to be stored in shift registers. The circuit should start with the least significant bits of each number and ...
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1answer
64 views

FSM for predesignated process (How to draw the state diagram)

let me start by saying this involves some homework problems so if you could help guide me a bit I would greatly appreciate it. I have been working with finite state machines for a bit in my course ...
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0answers
56 views

Parallel-in, parallel-out, universal shift register

I am trying build circuit of parallel-in/parallel-out universal shift register. I have found circuit in the Internet. Here it is I have tried to do this using MicroCap , but it doesn't work as ...
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0answers
42 views

Continuous Wave with flip-flops

What I'm going for is imagine 6 LED outputs, every other one on. (Off first) What I need to have happen is after I toggle on the 1 input to 1, it sets off a chain reaction, like a wave, where every ...
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1answer
66 views

Truth Table for JK flip-flop circuit?

Given a JK flip-flop circuit (using a D flip flop with a 2 by 1 MUX) how can I derive a truth table from this circuit? D = JQ' + K'Q Note: This is NOT a homework question. I just simply want to ...
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1answer
71 views

Does the output of JK Flip Flop toggle continously?

As given in most of the texts and online resources, the JK flip-flop requires a clock signal with an edge detector circuit so that the flip flop will be sensitive to the inputs only when the clock ...
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76 views

flip flop transfer function

Can same one explain me, if possible, how to get the equation of the transfer function for flip flop like the one below and hence get a plot like this
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1answer
134 views

Can someone explain to me what the 1s catching problem is in the Master Slave Flip Flop?

I have read the explanation in my textbook but I feel that they are too complex and no matter how much I try to understand it I don't seem to get what the difference is when the 1s complement occurs. ...
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1answer
62 views

How to toggle a reset in a counter made up of JK flip flops

I have been playing around with a small circuit which at the moment consists only of a counter made up of 3 JK flip flops. Like so: What I want to add is a reset input pin that will set the 3 LEDs ...
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1answer
34 views

connected d flip flop, propagation time = hold time?

When we connect two d flip flops, the propagation time and hold time have to be the same? or the propagation time have to be bigger than the hold time? I'm really confused please help!!
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2answers
249 views

Toggle two different LEDs with one T Flip flop

Imagine we have one green LED, one blue LED, power supply and resistors and grounds. We also have a switch. Can we toggle between the two different LEDs when the switch is pushed? If the blue LED is ...
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1answer
63 views

Purpose of T flip-flop in this circuit (LED)

In this circuit I try to toggle a LED on and off when a switch is pressed. Given the nature of the T flip-flop, when the switch is triggered, it toggles the clock and since T=1 always, it ...
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1answer
62 views

T-flip-flop without using a clock [closed]

Is it possible to create a T flip-flop without using a clock? I really need one, but I can't use one with a clock because it requires a signal shortener.
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51 views

Relay is not isolating properly its sorrounding circuit blocks

It turns out I've been building up an elevator for a project (at College). In general terms, everything appeared to be correct, regardless that I hadn't simulated each part. I decided to begin with ...
2
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3answers
460 views

Where does the power supply go in an SR Latch?

I understand how an SR Latch works: is S is 1, it will set Q to 1. If R is 1 it will set Q to 0. If both S and R are 0, the value of Q should remain unchanged (right?). So the circuit has these ...
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1answer
182 views

What is reset, preset and clear in a counter circuit?

I know this is a basic question. But I want to know the use of Reset, Preset and Clear in a Counter circuit. How do I use them? An example would be appreciated.
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4answers
254 views

ICs Powering On With Random Values

I've been prototyping a circuit for a first year university engineering project and I've been running into some problems with one section of the circuit that has really stumped me. Basically the flip ...
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1answer
63 views

Microcontrollers [closed]

Is there any other way of interfacing a push button with a LED but not directly with the micro controller? I would like to operate the LED in both method(push button as well as micro controller ...
2
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2answers
362 views

Setup Time, Hold Time - What is the underlying principle for having them?

I'm learning about setup time and hold time of a FF connected to a bus. But the textbook fails to explain exactly why are those needed in an operation. Isn't a FF always powered on and attentive to ...
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1answer
47 views

Is a D Type Edge triggered Master Slave flip flop considered a 1bit memory cell?

So in class we talked about how a D-type edge triggered flip flop is considered a 1bit memory cell. I think this is the same for a D-type latch. My question is, since a D-type edge triggered master ...
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1answer
125 views

D flip flop simulation: which simulation output is right?

I have always wondered, what is the right solution to the D flip flop when the input changes right at the rising edge of the clock? I have found two solutions of these online but have no clue which is ...
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195 views

How to create JK flip flop in proteus 8

I want to create a JK flip flop in Proteus 8.0 ISIS simulation tool. This is what I tried, but the problem with this is that the outputs Q and Q' are always zero regardless of what I set J or K. ...